These studies focus on the biochemical genetics of virulence and antibiotic resistance in the gonococcus. Studies include definition of the mechanisms of competence in the gonococcus including study of competence defective mutants. The biochemistry of the cell surface is being studied both in competence defective mutants and in isogenic strains which are altered in their antibiotic resistance. The effect of antibiotic resistance on virulence particularly on response to the bactericidal effect of normal human serum plus complement is also being investigated. BIBLIOGRAPHIC REFERENCES: Sparling, P.F., Sarubbi, F.A., Jr., and Blackman, E.: The inheritance of low-level resistance to penicillin, tetracycline, and chloramphenicol in Neisseria gonorrhoeae. J. Bacteriol. 124: 740-749, 1975. Biswas, G., Comer, S., and Sparling, P.F.: Chromosomal location of antibiotic resistance genes in Neisseria gonorrhoeae. J. Bacteriol. 125: 1207-1210, 1976.